Soi3p/Rav1p functions at the early endosome to regulate endocytic trafficking to the vacuole and localization of trans-Golgi network transmembrane proteins.
Soi3p/Rav1p functions at the early endosome to regulate endocytic trafficking to the vacuole and localization of trans-Golgi network transmembrane proteins.
复制标题
Soi3p/Rav1p 在早期内体中发挥作用，调节内吞运输至液泡以及跨高尔基体网络跨膜蛋白的定位。
DOI：
10.1091/mbc.e03-10-0755
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发表时间：
2004
影响因子：
3.3
通讯作者：
Fuller,RobertS
中科院分区：
文献类型：
--
作者：
Sipos,György;Brickner,JasonH;Brace,EJ;Chen,Linyi;Rambourg,Alain;Kepes,Francois;Fuller,RobertS
SOI3was identified by a mutation,soi3-1, that suppressed a mutanttrans-Golgi network (TGN) localization signal in the Kex2p cytosolic tail.SOI3, identical toRAV1, encodes a protein important for regulated assembly of vacuolar ATPase. Here, we show that Soi3/Rav1p is required for transport between the early endosome and the late endosome/prevacuolar compartment (PVC). By electron microscopy,soi3-1mutants massively accumulated structures that resembled early endosomes.soi3Δ mutants exhibited a kinetic delay in transfer of the endocytic tracer dye FM4-64, from the 14°C endocytic intermediate to the vacuole. Thesoi3Δ mutation delayed vacuolar degradation but not internalization of the a-factor receptor Ste3p. By density gradient fractionation, Soi3/Rav1p associated as a peripheral protein with membranes of a density characteristic of early endosomes. Thesoi3null mutation markedly reduced the rate of Kex2p transport from the TGN to the PVC but had no effect on vacuolar protein sorting or cycling of Vps10p. These results suggest that assembly of vacuolar ATPase at the early endosome is required for transport of both Ste3p and Kex2p from the early endosome to the PVC and support a model in which cycling through the early endosome is part of the normal itinerary of Kex2p and other TGN-resident proteins.
